Flame colorants

ABSTRACT

A COMBUSTIBLE MIXTURE CMPRISING A FUEL AND A PHOSPHOROUS TRIFLUORIDE SUBSTITUTED METAL CARBONYL, AND A METHOD FOR FORMING THE MIXTURE ARE DISCLOSED, THE ADDITION OF THE CARBONYL TO THE FUEL BEING MADE TO IMPART COLOR TO THE FLAME UPON COMBUSTION OF THE FUEL.

United States Patent 3,627,489 FLAME COLORANTS Henry E. Alquist, Bartlesville, Okla, assignor to Phillips Petroleum Company No Drawing. Filed Aug. 21, 1969, Ser. No. 852,108 Int. Cl. C101 1/12 US. Cl. 441 R 7 Claims ABSTRACT OF THE DISCLOSURE A combustible mixture comprising a fuel and a phosphorous trifluoride substituted metal carbonyl, and a method for forming the mixture are disclosed, the addition of the carbonyl to the fuel being made to impart color to the flame upon combustion of the fuel.

This invention relates to flame colorants.

In one of its more specific aspects, this invention relates to materials includable in fuels to increase the visibility of the flame resulting from their combustion.

The nonluminosity of flames produced by the combustion of certain gases and hydrocarbons is well known. While nonluminous flames are frequently desirable, there are other instances in which it is desired that the flame be visible. This invention is directed to that purpose.

According to this invention, there is provided a combustible mixture of a fuel and a phosphorous trifluoride substituted metal carbonyl, the carbonyl being present in the fuel at the combustion of the fuel in an amount sufficient to impart visual detection to the flame.

The method of this invention contemplates the addition of compounds, hereinafter defined, and their mixtures to any material whose combustion produces a flame, for the purpose of producing a visually detectable flame upon combustion of the material.

In general, this invention proposes the inclusion of these compounds at the time of combustion, whether such inclusion is made to the fuel prior to its combustion or at the point of combustion.

This invention contemplates the use of phosphorous trifluoride substituted metal carbonyls as the flame colorant, these compounds having the general formula in which Me is a metal selected from the group consisting of iron, nickel, molybdenum, cobalt, chromium and manganese, m is the valence of the metal, and x has any value of from 1 to ml. Suitable metal carbonyls from which the phosphorous trifluoride substitutes can be derived are iron pentacarbonyl, Fe-(CO) nickel carbonyl, Ni(CO) molybdenum carbonyl, M0(CO) cobalt carbonyl, Co (CO) chromium carbonyl, Cr(CO) and manganese carbonyl, Mn (CO) Of these, the phosphorous trifluoride substituted compounds of Fe(CO are preferred.

The phosphorous trifluoride substituted compounds of iron pentacarbonyl are prepared by methods disclosed in the literature which generally involve reacting the iron pentacarbonyl with excess phosphorous trifluoride at temperatures of about 170 to 275 F. at about 200 to about 500 p.s.i. for about 18 hours. The reaction product, suitable for use in this invention, is a mixture of the phosphorous trifluoride substitutions having the general formulas 1 "e(CO) (PF in which x is defined as above, the compound being comprised of a mixture of homologs having an average composition in which x equals 2.

The amount of the phosphorous trifluoride substituted metal carbonyl which is introduced into the fuel as necessary to impart a color to the flame will depend upon the metal contained in the carbonyl. Generally, from about 0.01 to about 1 volume percent of the substituted metal carbonyl will be employed, preferably from about 0.05 to about 0.5 volume percent. For inclusion in propane, for example, about 0.1 volume percent of Fe(CO PF3 produces a visible red-yellow flame on combustion. Other percentages can be used, it being desirable that the phosphorous trifluoride substituted metal carbonyl have substantially the same vapor pressure as the fuel into which it is incorporated, particularly if the fuel is drawn as a vapor from a tank in which some part of the fuel is maintained as a liquid.

The metal carbonyls are incorporated into the fuel in any suitable manner. Since a large part of such fuels are liquids, the metal carbonyls can be introduced into the fuels either as liquids or as gases.

It is evident, of course, that these materials may also be introduced into the fuel at the burner, that is, at or near the point of combustion. In this method of incorporation, they are preferably injected as vapors under pressure.

It will be evident from the foregoing that various modifications can be made to the method of this invention. Such are believed, however, to be within the scope of the invention.

What is claimed is:

1. A combustible mixture comprising a fuel and a phosphorous trifluoride substituted metal carbonyl, said metal being selected from the group consisting of iron, nickel, molybdenum, cobalt, chromium and manganese and said carbonyl being present in a quantity sufficient to impart visual detection to said fuel upon combustion.

2. The mixture as defined in claim 1 in which said carbonyl has the formula Me(CO) (PF in which in is the valence of the metal and x has any value from 1 to m1.

3. The mixture as defined in claim 1 in which said carbonyl is present in an amount from about 0.01 to about 1 volume percent.

4. The mixture as defined in claim 1 in which said carbonyl has the general formula Fe(CO) (PF in which x has any value from 1 to 4 and an average value of 2.

5. The mixture as defined in claim 4 in which said fuel comprises propane and said carbonyl has the formula Fe(CO )PF 6. The mixture as defined in claim 5 in which said carbonyl is included in said propane in an amount of about 0.1 volume percent.

7. The mixture as defined in claim 5 in which said carbonyl has a vapor pressure substantially equal to the vapor pressure of said propane.

References Cited UNITED STATES PATENTS 1,954,865 4/1934 Danner 4467 X 2,845,338 7/1958 Ryznar et al. 445 3,004,836 10/1961 Thompson 444 3,414,390 12/1968 Riess et al.

DANIEL E. WYMAN, Primary Examiner C. F. DEES, Assistant Examiner US. Cl. X.R.

23368; 4467; 48l97 FM 

